well tonight was the night it went in and i must say what an easy install...the fitment was great and the pipe itself is very well made....now as far as the butt dyno tells me it has more low end power...though at highway speeds it seems a little slower not sure though i was only on it real quick and had 2 other people in my car i will see better tomorrow morning on my way to work...now it also sounds a lot different i have the cattman muffler and made my own b-pipe out of 2.5 stainless steal and it almost sounds like a chevy berreta and it did get a little louder. do you guys think it would be worth trying the stock pipe to see if it makes any differance in noise and power? i'll have to hit the dyno sometime soon to really tell without the Y i dynoed at 210hp and 221tq so i hope it improved but thats all for now

 

keep us posted- use same dyno as before please!

 

Please update w/dyno info. I am scheduling to install my y-pipe and WS-metallic catalytic convertor this coming Sunday.

 

Give it some time. When I first installed mine the power gains seemed minimal. It seemed to get faster, however, each time I drove it. I am very satisfied with the increased power.

 

Exact thing happened here with the increase in power. Now i've got to get the pipe to stop banging the black cross member below the cat.

 

If my Max sounded like a Chevrolet Berreta, i would go back to stock.

 

A stock 88 or so Beretta had a sweet sounding exh from the factory. It could still only muster up a 130 or so hp from the 2.8/3.1

Dave
02 Maxima SE
85 El Camino w/GN drivetrain

 

The Chevy Beretta sounded like azz and only got worse with age.

 

I am a big fan of the way the Beretta sounded, but that was on a beretta!!!! I am trying to keep my max as quiet as possible. snky snky

 

I have interesting theory to propose--tell me what you guys think and if you notice this:

I have the inherent "banging" with the Y, but only have it during wheel hop. Even with the 19s on 245s first gear blows off like nuttin, and 2nd holds half the time.

Something I have noticed is that when I get on it and it hops (and bangs) a couple a times, my gas mileage damn near immediately goes to **** (roughly 3-4 mpg decrease.) This is proven less with the dash 'meter' and more with several tankfulls. But I can literally watch the MPG decrease instead of increase at a steady speed---it's just nuts.

My theory is this----the loud banging of the Y is tripping the Knock Sensor and causing it to richen up the mixture and retard the timing (it feels like it's coming through the floor!) As long as I stay off the throttle in first gear and avoid banging the pipe, my mileage goes back to normal and performance increases. As soon as it starts banging, its right back down again for a period of time (miles.)

I'm going to remove the X-member (against my better judgement) to verify that is the contact point, and if it proves to be--I will then experiment with trying to space the bracket down to minimize (or avoid altogether) the contact between the two.

Thoughts??

 

after driving it for a while today i noticed that my 0-60 feels quicker and i can spin the tires without even trying my car is auto by the way and the highway is still the same now you guys that have had it a little while what b-pipe do you have? stock or aftermarket and what do yours sound like?

 

I'll be installing my Cattman Y and WS B pipes next week. I can't wait!
I bought the Warpspeed b-pipe cause it was on sale. It cost me $170 shipped.
It's not stainless steel, but aluminized steel. It comes as one piece and looks pretty good for the price. I think the WS and the Budget b-pipes are pretty much the same, except for the material used. I'm ok with the aluminized steel since it was a little cheaper and since I don't plan on keeping the Max for more than another 3 or 4 years.

I'll let you guys know how it turns out.

 

I will be installing my Cattman Y on Saturday. I will let you know my thoughts on Monday

 

maximamaybe you install the Y yet? what you think

 

He likes it, we put it on last night.

Cept for the banging it's all good. It takes a couple of days for the ECU to fully adjust.

 

Going to be installing my Cattman Y next week. Brian Catts, who has responded to all my e-mails in a very timely and professional manner, advised that my Y should be going out this Thursday....

I just recieved the SS grills (ordered thru Stillen) and will install those 2moro.....

 

The banging is annoying, but so is regular wheel hop in general. I am going to get a custom B-Pipe fabricated that is around 1" longer than the stock one. That will solve my problems I am sure. The power is definately there and seems to be improving with driving. Also, my exhaust note with the Powertech muffler sounds 350Z like. I am thrilled so far.

 

Has anyone contacted Brain Catts about the banging problem?

 

Assuming this is a Cattman y-pipe, Check your motor mounts, there is no pattern of the pipes we've been making for the last couple of years touching other parts. I literally haven't heard of a single clearance issue with a y-pipe (in the course of typical competetive driving) since we did the re-design. I'm not saying its impossible, but the only circumstances I can even imagine would be during wild wheel hop and I'd have to be convinced that is the y-pipe even then.

In extreme situations like wheel hop, I strongly advise getting some heavy duty motor mounts -- otherwise you will break things (major things, ultimately) doing this. I cannot imagine a circumstance that would put more extreme stress on the drive train.

Brian C Catts
Cattman Performance

 

I'm not familiar with the B-pipe you've selected, but since materials are not your concern, the primary question with a B-pipe is whether or not it has an adequate resonator. If the resonator is not large enough (and of adequate quality) you will never hear a quality sound from the car with a performance y-pipe because the tone will change to a harsh and raspy sound.

I would also note that we have separate dyno information available for the Cattman b-pipe, added after a Cattman y-pipe. It added an average of 3.4 hp between 3800-6300 rpm, and between 4-5hp through much of that range. No, it will not rip your cheeks off, but those are respectable results for a simple B-pipe. Together with the Cattman y-pipe, there was an average gain of 11.2 HP between 3800-6300 with peaks of 18-19hp. (all figures at the wheel)

Brian C Catts
Cattman Performance

 

[QUOTE=I literally haven't heard of a single clearance issue with a y-pipe (in the course of typical competetive driving) since we did the re-design.
Brian C Catts
Cattman Performance[/QUOTE]


When did you redesigned the y-pipe? Did you make the length longer to match w/the OEM's pipe? If so, what should be the correct length? I am somewhat concerned after reading and seeing the posted pics here that the y-pipe I got from you guys a couple of weeks ago may have fitment issue? Please address my question ASAP since I will get it install this weekend.

 

I've been giving this topic some thought.

In terms of clearance, we've sold quite a few of these new y-pipes and there were no visible clearance concerns when installed on the car. If you note the two individuals commenting on a banging sound, this is only occurring during "dump-the-clutch-off-the-line" launches when wild wheel hop is occurring.

When the car is doing that, things are moving around (the engine itself is flopping around 4-5") and stresses are occurring that go way beyond the design tolerances for the car -- in particular the motor mounts -- and those are allowing engine movement that we cannot work around. Nissan added big HP to the motor, but didn't do anything to the mounts, and they're nowhere near stiff enough. A recent thread indicated that a lot of people have gone through 2-3 sets of mounts in a year or two. There is no pattern like that in VQ30DE Maximas.

I think the key issue is that there is only one circumstance that is associated with this banging sound (that I, and apparently those who are experiencing it, are not certain is associated with the y-pipe) and that is extreme wheel hop in first gear. Drag racing requires a number of modifications to be done well -- the problem in this case is wheel hop and the solution is heavy duty motor mounts -- which will help with all the damaging stresses the drivetrain is being subjected to (snap an axle and you'll see what I mean).

It would be useful to be able to confirm the precise point of contact. I called friend with an 03, Cattman Y and a catback exhaust. He races quite competently and is well into the 13s with minimal mods. He gets no noise from his y-pipe, but did get some from other sections of the exhaust system during hard launches. After adding a strategically placed extra hanger on the catback, that noise went away. I would also add that he gets very good 60' times on street tires, and with "low-hop" launches. He also mentioned that dropping the inflation of the tires to 25 lbs helps with the hp too, but I'd think that most people would be aware of that.

Brian C Catts
Cattman Performance

 

[QUOTE=VMaximus02][QUOTE=I literally haven't heard of a single clearance issue with a y-pipe (in the course of typical competetive driving) since we did the re-design.
Brian C Catts
Cattman Performance[/QUOTE]


I apologize for not being clear. As I began reading the thread, I was thinking of our y-pipe series in general and clearance problems of this type that we used to have years ago with a different design. That general issue was eliminated when we changed suppliers and re-designed all the y-pipes we were making at that time (about 2.5 years ago).

There has been no re-design of the 02-03 pipe, nor is there any need for one. Regarding the length issue you bring up, there is no merit to it - you have misunderstood someone else's comment - he was talking about lengthening his B-pipe, though I don't understand why. Our pipe has the same bolt-up dimensions as the stock pipe we modelled from, meaning that the positioning of the three flanges in 3D space are the same between the two.

What you have read (I can now see) is not a source of concern because it is 1) not a fitment issue, and 2) it is impossible to prevent the end of the y-pipe from moving up and down during wheel hop unless you upgrade your motor mounts.

Brian C Catts
Cattman Performance

 

I am not bagging on the Y pipe design. Just stating fact from 2 seperate vehicles. The Y-pipe is shorter and I agree that it only happens when wheel hop. The problem(don't get me wrong, I love the added power) is that the car tends to hop more during launch. It also hops on a quick 1-2 shift. I get banging at the same time. As far as the cattman B-Pipe or catback I am betting that the bends are not exactly like OEM therefore it might provide more clearance. All I think we need is around 1" added to my B-Pipe to make things not bang.

Here are some pictures we took illustrating our issue. 2 cars. Exact same problem.
Here are both pipes side by side----notice the difference in length overall of the new pipe:


Not too big a deal....yet. Here is the location of the stock resonator with the stock y-pipe.


Here is the location of the stock resonator with Cattman y-pipe. Note how much farther forward it sits: (Use the front lip of the resonator as a reference point.)


Still not too big a deal, right?? Here is the after effect after a month of driving:

 

After reading back through some of the posts, I've realized that the theory on the banging is that something is hitting the little cross pieces that go under the exhaust to catch if if the bolts come loose (know of any other manufacturer that does this?).

Due to terminology, I suppose, I had the impression that someone thought the y-pipe was hitting the crossmember that supports the engine. That would be a fitment problem. What I realize is being described (now) is not.

For an oversize pipe to hit the little exhaust catchers is NOT a fitment issue, and has absolutely nothing to do with the y-pipe design. It IS an inherent problem as some have stated (meanging it has nothing to do with our y-pipe design and cannot be avoided), as it is caused SOLELY by the engine's front-rear movement during a violent launch. The only way to restrain the degree of movement is to install HD motor mounts.

I'd like to try to gently point out that this thread is a great example of a small amount of useful information turning into a larger amount of misleading information.

Fact: there is nothing wrong with the design of the y-pipe because with the stock mounts in place the engine will flop around, exaggerating that movement by the time you get to the end of the y-pipe, and since its in an enclosed space it hits the little crossbracket that is under the exhaust (and can easily be moved by spacing with washers or taken off entirely since it solves little purpose).

Result of this thread: Totally unfounded impressions that the y-pipe doesn't fit, that the clearances are not adequate, and that its too short (that's really a bizarre one).

Please you guys, this kind of negative publicity is damaging and unfounded. Its nobody's fault in particular, its just the result of collective misimpressions and conclusions made without adequate consideration of the facts (or realizing there were not sufficient facts to draw a conclusion). I know it happens all the time, but for those of us in the business it can have immediate and damaging results. Bad information take on a life of its own. I'm still explaining to people that Cattman Performance solved the bees-in-a-can y-pipe noise -- never mind the fact that we were the first company to solve this about four years ago, and we've improved on that several times since.

Brian C Catts
Cattman Performance

 

Damn...I have never seen by a vendor....but I think I can now mark that off my list. You guys need to pay attention to what he is saying and be sure about stuff before you start trashing it. A few GLARING examples would be Stillen and Technosquare.

 

I am not trying to be an *** or complain about the product, but if you look at the following pictures, you can see that the resonator sits further to the front of the car with the cattman Y.

Not too big a deal....yet. Here is the location of the stock resonator with the stock y-pipe.


Here is the location of the stock resonator with Cattman y-pipe. Note how much farther forward it sits: (Use the front lip of the resonator as a reference point.)


Motor mounts would play a big part in improving the movement and making it a non issue.

 

Don't get me wrong Cattman, I like the pipe and think the quality is good---that being said----the problem we are experiencing IS due to the shortness of your pipe.

Yes, if I didn't have the 'give' of the stock motor mounts it would most likely not be an issue. But I can tell you this for sure: I had NO clearance issues with the stock stuff. Your pipe is shorter overall in length which pulls the ENTIRE cat-back assembly forward ~5/8 of an inch, which in turn cause a tighter clearance with the STOCK B-pipe and the frame--therefore decreasing the tolerances of the stock cat-back.

I have no bang during launch, only during ANY kind of wheel hop---it bangs before I can even get out of the throttle. The pics you see above are of my car. My wheel hop is not that bad nor do I routinely attempt it (I can't afford to replace 19" tires all the time.)

There are NO clearance issues of the y-pipe itself, only the remaining stock cat-back after the y-pipe install.

This isn't to bash you or your product, only to explain the potential problems to expect given the same scenario.

Steve

Here is my original thread on the problem.

 

I realize that you're happy with the y-pipe and not intentionally bagging it, but since the information you've laid out is flawed (no disrespect, its just not right), it will ultimately have some negative effect.

Perhaps the key point here is that the y-pipe is NOT shorter, get a tape and check. The pics are misleading, because its difficult to compare two arcs laid next to each other (there's a common optical illusion that involves arcs laid next to each other that seem to be of different lengths, but are equal). Don't look, simply check the length or, better yet, take another look at the before and after pics (see next paragraph).

Second, the pic of the resonator only shows that the resonator is positioned farther back, but that's hardly the point is it? You can see from the pictures that the front end of the B-pipe where the cat flange meets the B-pipe flange is in the same place. The resonator doesn't need to be in the exact same position along the B-pipe length, but there is good reason for the flanges to be in the same position, and they are. This clearly demonsrates that the y-pipes are of equal length.

I'm not sure how another inch on the b-pipe will help, but it obviously has nothing to do with the y-pipe. There is typically a little adjustement that need to be done to hangers when a catback is installed and perhaps that could have been done better during intitial installation (though it could have been fine), but Ithink the key solution would be to strategically place an additional hanger on the exhaust (not y-pipe). A friend of mine did this because his exhaust would rattle during wheel hop and it completely solved it.

Also, consider these other variables, which could have a significant influence on this issue:

If you have something other than a Cattman muffler I don't know how well it fits and every part of the exhaust system influences the position of the others. The excessive motor movement due to inadequate mounts will toss the entire exhaust system around to a greater degree than any undercar clearance allows, and the dent in your b-pipe is at least partially attributable to that. Its obvious from the amount of clearance in the picture that there is no contact during normal driving.

Brian C Catts
Cattman Performance

 

Thanks for your input on the subject. Duly noted.

 

NO NO NO, I'm not trying best anyone in this discussion, I'm not mad at anyone, there is nobody in this thread that I feel is intentionally attacking me or my company, I saw what I thought were some worthy observations, but the thread ran wild and the cause and effect conclusions are way off base.

So I had to speak up.

If anything I've said seems confrontational, that is not my intent and I apologize sincerely.

Brian C Catts
Cattman Performance

 

brian catts is so nice.

btw.. ur ypipe for us 2k2-2k3 guys ROCKS!!!!! i love it.. i've had it on for about 5-6000 miles now... no problems whatsoever...

 

There is a definite reason that the new exhaust will not have the clearance of the old one -- every component is significantly larger in diameter and they are all operating (and moving around) in confined spaces. As I indicated in another email, if the mid-pipe is hitting the little crosspieces underneath, either extend them with washers or remove altogether. If that's not the point of contact, find a strategic spot and install an additional exhaust hanger. We replicated the stock hangers, but they are obviously not adequate under these racing circumstances and we know from other customer's experience that this is an effective solution (I can try to get pics).

The issue with wheel hop and motor mounts is that it shouldn't be so easy to induce on these VQ35 cars -- the mounts are not just the cause of overly violent wheel hop during hard launches, they cause the milder wheel hop that you are referring to -- that shouldn't be happening at all (you should really have to romp on the car to cause wheel hop, but with the stock mounts its much easier).

Brian C Catts
Cattman Performance

 

Cattman, you are flat wrong on the shortness of the pipe. The Pictures CLEARLY show how the entire cat-back sits further forward. The only difference is that the 'after' picture does not have the cross-brace installed. Note the placement of the resonator compared to the heat shield.

Yes, the picture of the pipes side by side could be confusing, but the before and after pics ON THE CAR are plain as day with the B-pipe location. Dispute away.

I have nothing to gain by making this up. I'm simply stating fact. You can deny it all you want but the fact remains that the pipe relocates the cat-back a small amount---and that is enough to cause contact with the body under stress.

Most the aftermarket cat-back systems I've seen are bent in a different area that the stock one and I doubt there would be a contact issue with one of those---but with the stock system, it makes contact.

Debate away.

 

Cattman : Do you sell motor mounts?

If not, where can we get some? I'd like to get this fixed before I mess with your exhaust....

 

http://www.cattman.com/prod_traction.html

 

No debate, but I must admit that I've made an error. So many of these discussions would work better if we were a group of people in the same room, and I've misunderstood something that partially affected my replies.

I'm reacting to input from several different people, but my first reaction to your pics reflected the misimpression that you had swapped out the y-pipe and b-pipe at the same time. Based on that impression I'd said that it looked like the resonator changed positions (thinking they were two different B-pipes), but that the flange remained in the same position. [That must have seemed like a pretty bizarre conclusion.] Following your comments, and examining the pics more closely and seeing that they are the same mid-pipe, I concede your observation. The flanges do not appear to change positions in the two pics, but they're at the edge of the photo and if the b-pipes are the same, its clear that if the resonator position moved, the whole thing did.

Now, does that mean that we built it shorter than the stock pipe we were modelling off of? I still find that an unlikely explanation because I know how precisely these are designed, and that once the manufacturing fixture is made, we put the stock pipe in to confirm fit.

So, why the difference? I cannot say with certainty, but I try to think logically and so propose a hypothesis. We were working from a brand new y-pipe, ordered through the dealer and never installed on a car. If you're familiar with the structure of a flex section, its basically like an accordian, with ribbed bellows inside that contain the gasses but allow the flex to bend without cracking. The outside braided metal fabric keeps the accordian-like liner from stretching all the way out, but the braiding does stretch somewhat and when you think about it, it only make sense that it would gain some length on the car as a result.

The flexes we use, however, could only stretch very little, if at all because the liner is interloc material (like what protects a pay phone cord) and will not stretch longitudinally like the braiding on the outside of the flex.

This does not affect the validity of your observation, but it provides a possible explanation for something that I could not accept (because I knew differently) -- that the y-pipe was made shorter than the part we were modelling after.

All of this said, the fact remains that we've sold almost 50 of these so far, and most owners are not having an issue with non-y-pipe exhuast parts touching anything -- that takes nothing away from the issues these guys have run into, but I would still insist that they can be overcome with better motor mounts and adding an extra exhaust hanger (beyond stock) to the mid-pipe to better captivate its movement.

Brian C Catts
Cattman Performance

 

Keep in mind---urethane mounts have almost no deflection and will transfer all vibration into the vehicle.

I have been pushing Energy Suspension to make urethane inserts for our cars but this is the most recent response I got from them:

"Steve - We are moving forward at the pace of molasses uphill in the winter
time. I cannot seem to get new products into the pipeline here with any sort
of timeliness at all. The Maxima 3.5 mounts are likely still a year off! I
hate being the bearer of bad news - but I thought I'd better let you know
just how slow this stuff is going here. Sorry about that - Hoyt Vandenberg"

 

We may be more the exception than the rule, and like I've stated, it's not too big a deal with me, since I plan to get aftermarket cat-back at some point anyway. I was merely trying to state a potential issue for others with the same configuration. The stock piping makes a 90-degree bend at the contact point, and so far all the aftermarket kits I've seen pics of have a shorter turn (two 45-degree turns or one big-sweeping turn) which seem to avoid that area altogether.

I wish I could live with the extra vibration of the urethane mounts. That alone would solve most the wheel hop.

 

Well, I didn't want to seem to be manipulating a complaint into a sales opportunity, but Cattman Performance has been selling HD urethane mounts for years because we sponsored the development. Originally for the 95-99, Nissan held the design, and they are being installed on 95-03 cars with great results. The mounts are totally new, not rebuilds or recasts (customers who've attempted to recast their own mounts are one of our biggest sources of demand for these). Perhaps most importantly, they are guaranteed for life by Place Racing.

As noted, they transmit more vibration through the body, but I quickly got used to that (adjusting the idle helps a lot) and the having the engine strapped down instead of flopping all over the place gives a whole different feel to the way the vehicle behaves.

Brian C Catts
Cattman Performance